1. Field of the Disclosure
Exemplary embodiments relate to a display device.
2. Description of the Related Art
The importance of display devices has recently increased with the growth of multimedia. Various types of display devices such as liquid crystal displays (LCDs), plasma display panels (PDPs), field emission displays (FEDs), and organic light emitting devices have been put to practical use.
Among them, the organic light emitting device has come into the spotlight as a next generation display device because of the advantages of the organic light emitting device. The organic light emitting device has better visibility than a cathode-ray tube, has low average power consumption, and generates less heat. The organic light emitting device has fast response speed, for example, about 1 ms, has low average power consumption, and does not have a viewable angle problem because the organic light emitting device is a self emitting device.
Such the display device is driven based on one of a passive matrix method and an active matrix method using a thin film transistor. In the passive matrix method, anodes and cathodes are formed orthogonally, and the display device is driven by selecting predetermined lines. On the contrary, in the active matrix method, a thin film transistor is connected to each pixel electrode, and the display device is driven according to a voltage maintained by a capacitor connected to a gate electrode of the thin film transistor.
The display device includes a display area for displaying images and a driver for driving the display area. The driver includes a printed circuit board (PCB) including parts for generating various control signal and data signals. The driver also includes a driver integrated circuit (IC), which is connected to the PCB and the display panel, for applying a signal to lines of a display panel. The display device may be classified into a chip on glass (COG) type, a tape carrier package (TCP) type, and a chip on film (COF) type according to a method of packaging the driver IC into a panel.
Pad electrodes on a pad area may be electrically connected to the driver by a conductive adhesive layer.
The pad area and the driver may be formed by coating an anisotropic conductive film (ACF) on the pad area and compressing the driver on the pad area. However, the conductive adhesive layer was coated on the pad area corresponding to the size of the driver. That is, the conductive adhesive layer was coated only in consideration of the adhesive function.
The pad electrodes inside the pad area were easily eroded by moisture and oxygen thereby deteriorating the reliability of a display device.